1. Field of the Invention
The present invention relates to an automatic parts handling apparatus for successively feeding and housing a plurality of parts to and from an apparatus for successively assembling and processing the parts.
2. Description of the Prior Art
With the rapid progress of various techniques, apparatus of various types including many information processing devices have reduced life cycles while being made increasingly diversified and highly efficient. Market needs for production of such devices require elimination of uncertain manual operations, stabilized production processes by mechanization, and thus less scattered product quality, reduced production lead time, and reduced cost of manufacture. An automatic parts handling apparatus is known to promote automation to achieve such needs.
One known arrangement of an automatic parts handling apparatus will be described with reference to FIGS. 1 to 4.
Conventionally, in successively feeding a plurality parts to a parts processing apparatus, parts 2 are first lined up on a pallet 1 as shown in FIG. 1. A plurality of such pallets 1 in turn are stored or positioned on shelves 3. The pallets are taken out of order upwardly or downwardly from the shelves 3 and are fed to a processing apparatus (not shown) by means of a feeding device (not shown).
However, with such arrangement of the pallets 1 and the shelves 3 for feeding parts, it is difficult to automate the devices employed to remove the parts containing pallets from the shelves 3 as well as to position the parts containing pallets on the shelves 3. Therefore, it has been difficult to automate this type of parts feeding device.
Japanese Patent Application No. 59-148556 discloses an automatic parts handling apparatus for automating a parts feeding operation. In the following, such known automatic parts handling apparatus will be described with reference to FIGS. 3 and 4, the former figure being a side elevational view of the apparatus and the latter illustrating a sequence of operations of the apparatus. This prior apparatus includes boxes 4 housing respective pallets 5 and having hook portions 4a formed therearound. Parts 6 are positioned on pallets 5, and a plurality of such units are accumulated in a stack. The accumulated units separated from each other by means of a separator 7 with the aid of the hook portions 4a, and any one among a plurality of the separated units is removed by means of a lifter apparatus 8. The thus removed unit is moved to a prescribed position or an elevator apparatus 10 by means of a conveying apparatus 9. The elevator apparatus 10 lifts only the pallet 5 placed in the respective box 4 and feeds the parts 6 to an automatic parts processing apparatus.
When feeding of the parts 6 is completed, the empty box 4' is lowered and discharged by means of a discharge arm 1. Thereafter, the empty box 4' is returned to a prescribed recovery position with the aid of the lifter apparatus 8.
Such known automatic parts handling apparatus however is adapted to convey a plurality of parts by use of both sheet metal boxes and pallets. Accordingly, the structure of the automatic parts handling apparatus is complicated and costly because of the relatively large number of components required. Moreover, since the separator apparatus, the lifter apparatus, the conveying apparatus and the elevator apparatus are arranged side by side, the handling apparatus has a large outer size. Furthermore, empty pallets and pallets containing parts are accumulated at the same position. Accordingly, the space available to accommodate a pallet exchange operation, e.g. by means of an unmanned car, etc., is reduced, with the resultant possibility that a production line may be stopped in dependence upon the timing of parts exchange effected by the unmanned car, etc.